Modeling of Rocks with Spatial Distributed Fractures by Random Medium Theory

By using the spectrum expanding theory of random processes and Hudson's crack model,we developed a random medium model for rocks with spatial random distributed number density of cracks. This model could connect the micro-parameters of the cracks with the macro- mechanical properties, and can be effectively applied to model the real inhomogeneous medium. Numerical example indicates that the random distribution characters could be different for different elastic constants under the same random distribution of number density of cracks. By changing the value of the autocorrelation length pair, it is possible to model the difference of the distribution in the two coordinate directions. Numerical modeling results for seismic wave propagating in rocks with random distributed fractures using a staggered high-order finite-difference (SHOFD) are also presented.

Influence of features of natural soft clay on behaviour of embankment

The influence of different features of natural soft clays,namely anisotropy,destructuration and viscosity,on modelling the time-dependent behaviour of Murro embankment was investigated.The newly developed elasto-viscoplastic models were enhanced for determining viscosity parameters in a straightforward way and adopted for the finite element analysis.The same set of common parameters determined from conventional triaxial and oedometer tests was employed for all models,with additional parameters required for representing different soil features.The finite element predictions by using models coupled with BIOT's consolidation theory were compared with each other and with field data for settlement,horizontal displacement and excess pore pressures.In addition,the stress paths under the embankment loading were also compared with each other to improve the understanding of the effect of different soil features.All simulations demonstrate that all three features significantly influence the predictions.As a consequence,accounting for soil features needs to be carefully considered when they are applied to a construction site.

Finite element formulation of active constraining layer damping plate using laminate theory

A new finite element modeling method has been developed using laminate theory in a virtual work principle for active constraining layer damping plate. The frequency dependent modulus of viscoelastic material is described by introducing a few dissipation coordinates, known as GHM (Golla-Hughes-McTavish) method, a standard linear system with constant coefficient. The effectiveness of this method is validated by experimental model. Compared with conventional methods, this method can reduce a number of degrees of freedom and improve accuracy, provides a good model for analogous configurations.

Topological Properties of Complex Networks with Different Types of Nodes

Nodes play different roles or have different functions in many natural and social networks.In this paper,a simple model with different types of nodes and deterministic selective linking rule is proposed.The structural properties by theoretical predictions are investigated that the given model exhibits a power-law distribution.

Quotient space model based on algebraic structure

In the quotient space theory of granular computing,the universe structure is assumed to be a topology,therefore,its application is still limited.In this study,based on the quotient space model,the universe structure is assumed as an algebra instead of a topology.As to obtain the algebraic quotient operator,the granulation must be uniquely determined by a congruence relation,and all the congruence relations form a complete semi-order lattice,which is the theoretical basis of granularities ' completeness.When the given equivalence relation is not a congruence relation,it defines the concepts of upper quotient and lower quotient,and discusses some of their properties which demonstrate that falsity preserving principle and truth preserving principle are still valid.Finally,it presents the algorithms and example of upper quotient and lower quotient.The work extends the quotient space theory from structure,and provides theoretical basis for the combination of the quotient space theory and the algebra theory.

Worldviews, Media Use, and Attitudes Toward Science in 1957： A Structural Equation Test of Cultivation Theory

A structural model of cultivation theory is tested by using a national data set from 1957, before television became a dominant medium in the United States. Support is found for the basic tenet of cultivation theory, namely, that media use shapes people＇s perceptions and beliefs. Print media use predicts one＇s worldview, both of which predict attitudes toward science. By examining attitudes toward science before television became a dominant medium, this study extends the theory beyond the field＇s primary research focus on the relationship between television and violence.

Application of Structuration Theory and Activity Theory in Enterprise Resources Planning Systems Implementation for Universities

An integration of organization culture in the conceptualization and development of Enterprise Resource Planning Systems （ERPs） is critical for an organization to reap potential benefits of the system. In this paper, the authors present an analytical approach through the Structuration Theory： How a university can assess its culture for the purposes of design and development of the ERPs. The authors extend the Structuration Theory by integrating it with the Activity Theory to provide the means of evaluating the activities that the system is to perform. The modified Orlikowski model is applied to depict the relationship between institutional properties, human agents, and technology in the university setup and how this offers a more inclusive approach to ERP systems development and implementation.

Mobility in Driven Frenkel-Kontorova Model

The transport properties in a kind of simple system are studied within the framework of a generalized Frenkel Kontorova model where the chain is composed of two kinds of atoms. Its studied mobility includes two aspects: the velocity mobility B v and the momentum mobility B m . The effective system temperatures for the two subchains, T e 1 and T e 2 are defined, respectively. For the underdamped case, the regime of nonlinear response becomes wider and more "steps" occur when the value of m increases. For m = 1, T e 1(F) = T e 2(F) . For m >1, T e 1(F) > T e 2(F) and the difference increases with the increase of m . The momentum transportation shows very different behavior from that of the velocity transportation. Within a prescribed intermediate "steps" of B v(F) or B m(F) , both of them decrease with the increase of F and B m(F) decreases more quickly. For the case of overdamping and nonzero temperature, the hysteresis interval becomes thinner and the transitions become smoother. The increase of m makes the hysteresis thinner and the transitions smoother. When T is high, all the transitions are smeared out, and the diatomic effects become unimportant. We expect these results contribute to the understanding of the atomic processes occurring at the interface of two materials when they are brought together and moved with respect to one another.

Topology of Prion Proteins

A conformal structure of a prion protein is thought to cause a prion disease by S.B. Prusiner＇s theory. Knot theory in mathematics is useful in studying a topological difference of topological objects. In this article, concerning this conjecture, a topological model of prion proteins （PrPc, PrPsc） called a prion-tangle is introduced to discuss a question of whether or not the prion proteins are easily entangled by an approach from the mathematical knot theory. It is noted that any prion-string with trivial loop which is a topological model of a prion protein can not be entangled topologically unless a certain restriction such as ＂Rotaxsane Property＂ is imposed on it. Nevertheless, it is shown that any two split prion-tangles can be changed by a one-crossing change into a non-split prion-tangle with the given prion-tangles contained while some attentions are paid to the loop systems. The proof is made by a mathematical argument on knot theory of spatial graphs. This means that the question above is answered affirmatively in this topological model of prion-tangles. Next, a question of what is the simplest topological situation of the non-split prion-tangles is considered. By a mathematical argument, it is determined for every n 〉 1 that the minimal crossing number of n-string non-split prion-tangles is 2n or 2n-2, respectively, according to whether or not the assumption that the loop system is a trivial link is counted.

Research on angle-dependent to mographic static correction

Reflection data in CMP has influenced seriously in static calculations,especially in some highly weathered and structurally altered circumstances. Because of static correction in the existed problems and requests,the authors studied the angle dependent tomographic static correction,and discussed its basic theory, including the establishment of forward model,the calculation theory of tomography and tomographic static correction. The usage of theoretical models and practical information on the method has been validated. The results show that using these methods to calculate static correction in a complex area,the quality of static correction is greatly improved.

抛物线中的一类直线解析式及其应用

抛物线中有很多美好的基本结论,这如同平面几何中的基本图形一样,它们在解题教学中发挥着不可估量的作用.本文研究抛物线中的一类直线解析式,并通过相关例题剖析其应用,希望能够给一线数学教师和毕业年级学生中考复习提供帮助.

CR THEORY AND RHETORICAL DIFFERENCES BETWEEN CHINESE AND ENGLISH WRITING

CR theory focuses on the study of academic or professional writing across different cultural settings. One recurring question of CR theory in the Chinese ESL context is whether the rhetorical differences in organization, modeling, and syntax between Chinese and English writing indeed exist, and if so how they affect ESL writing. Through examining the controversies surrounding these rhetorical differences along with a brief review of the development of CR theory and pedagogical implications, this paper contends that the study of CR theory has exerted beneficial influences on L2 writing.

The Game Theoretical Approach for Multi-phase Complex Systems in Chemical Engineering

This paper explores the application of noncooperative game theory together with the concept of Nash equilibrium to the investigation of some basic problems on multi-scale structure, especially the meso-scale structure in the multi-phase complex systems in chemical engineering. The basis of this work is the energy-minimization-multi-scale （EMMS） model proposed by Li and Kwauk （1994） and Li, et al. （2013） which identifies the multi-scale structure as a result of ＇compromise-in-competition between dominant mechanisms＇ and tries to solve a multi-objective optimization problem. However, the existing methods often integrate it into a problem of single objective optimization, which does not clearly reflect the ＇compromise-in-competition＇ mechanism and causes heavy computation burden as well as uncertainty in choosing suitable weighting factors. This paper will formulate the compromise in competition mechanism in EMMS model as a noncooperative game with constraints, and will describe the desired stable system state as a generalized Nash equilibrium. Then the authors will investigate the game theoretical approach for two typical systems in chemical engineering, the gas-solid fluidiza- tion （GSF） system and turbulent flow in pipe. Two different cases for generalized Nash equilibrinm in such systems will be well defined and distinguished. The generalize Nash equilibrium will be solved accurately for the GSF system and a feasible method will be given for turbulent flow in pipe. These results coincide with the existing computational results and show the feasibility of this approach, which overcomes the disadvantages of the existing methods and provides deep insight into the mechanisms of multi-scale structure in the multi-phase complex systems in chemical engineering.

A new many-body potential with the second-moment approximation of tight-binding scheme for Hafnium

In this work,we develop a new many-body potential for alpha-hafnium(α-Hf)based on the second moment approximation of tight-binding(TB-SMA)theory by introducing an additional Heaviside step function into the potential model and a new analytical scheme of density function.All the parameters of the new potential have been systematically evaluated by fitting to ground-state properties including cohesive energy,lattice constants,elastic constants,vacancy formation energy,structure stability and equation of state.By using the present model,the melting point,melt heat,thermal expansion coefficient,point defects,and low-index surface energies ofα-Hf were calculated through molecular dynamics simulations.Comparing with experiment observations from others,it is shown that these properties can be reproduced reasonably by the present model,some results being more consistent to the experimental data than those by previous suggested models.This indicates that this work is sutiable in TB-SMA potential for hexagonal close packed metals.

LEARNING CAUSAL GRAPHS OF NONLINEAR STRUCTURAL VECTOR AUTOREGRESSIVE MODEL USING INFORMATION THEORY CRITERIA

Detection and clarification of cause-effect relationships among variables is an important problem in time series analysis. Traditional causality inference methods have a salient limitation that the model must be linear and with Gaussian noise. Although additive model regression can effectively infer the nonlinear causal relationships of additive nonlinear time series, it suffers from the limitation that contemporaneous causal relationships of variables must be linear and not always valid to test conditional independence relations. This paper provides a nonparametric method that employs both mutual information and conditional mutual information to identify causal structure of a class of nonlinear time series models, which extends the additive nonlinear times series to nonlinear structural vector autoregressive models. An algorithm is developed to learn the contemporaneous and the lagged causal relationships of variables. Simulations demonstrate the effectiveness of the nroosed method.

A semi-analytical method for the analysis of pile-supported embankments

In this paper,a semi-analytical method for the analysis of pile-supported embankments is proposed.The mathematic model describes the cooperative behavior of pile,pile cap,foundation soil,and embankment fills.Based on Terzaghi's 1D consolidation theory of saturated soil,the consolidation of foundation soil is calculated.The embankments with two different types of piles:floating piles and end-bearing piles are investigated and discussed.The results of axial force and skin friction distributions along the pile and the settlements of pile-supported embankments are presented.It is found that it takes a longer time for soil consolidation in the embankment with floating piles,compared with the case using end-bearing piles.The differential settlement between the pile and surrounding soil at the pile top is larger for the embankment with end-bearing piles,compared with the case of floating piles.

Identifying Factors of Integrated Industry Based on the Complex Systems Theory

First of all, the definition of integrated industry is given from the perspective of complex systems; secondly, the factors of integrated industry are identified by the application of the hierarchical structure model of the complex systems theory; thirdly, the characteristics of integrated industry are analyzed; finally, the problems which should be paid attention to in the process of integrated industry enumerated.